Pump construction



June 13, 1961 sc 2,988,003

PUMP CONSTRUCTION Filed July 1, 1960 2 Sheets-Sheet 1 INVENTOR. JosephM. Schmied AT ORNEY June 13, 1961 J. M. SCHMIED 2,988,003

PUMP CONSTRUCTION Filed July 1, 1960 2 Sheets-sheet 2 Fig. 6

SUPPLY TANK MIXING TANK INVENTOR.

Joseph M. Schmied B i" I y E Q I Fig. 5

AT ORNE Y 2,988,003 PUMP CONSTRUCTION Joseph M. Schmied, 275 CastenadaDrive, Millbrae, Calif. Filed July 1, 1960, Ser. No. 40,247 11 Claims.(Cl. 103-37) This invention relates to a pump construction and moreparticularly to a rotary type pump for moving a flowable product inwhich product displacement may be varied selectively from apredetermined minimum or Zero to a predetermined maximum. That is, thesubject pump construction is adapted for constant or selectivelyvariable product displacement between predetermined limits. Furthermore,the subject pump during operation is capable of effecting productdisplacement without surging or pulsation.

A further important feature of this pump development resides in the factthat the same is selectively adjustable so that the direction of productflow therethrough may be rapidly and easily reversed. As a result, thesubject pump is particularly well suited for use in the mixing of two ormore flowable products as will be described hereianfter.

The pump of this invention is simple in construction and comprisescomparatively few component parts so that the same may be inexpensivelymanufactured with minimum machining required. In addition, the pump isinexpensive to operate and may be actuated by any suitable power source.

Summarizing this invention by stating certain of its objects, thepresent invention includes the provision of a pump construction in whichproduct displacement therethrough may be varied within predeterminedlimits; the provision of a pump in which the direction of productdisplacement may be reversed by a simple pump adjustment; the prowsionof a pump which is capable of acting as its own valve to terminateselectively product flow; and the States Patent C) provision of a pumpin which deformable and resilient pumping elements are employed in aproduct displacement passage for effecting product displacement duringpump operation.

These and other objects will become apparent from a review of thefollowing specification, for an understanding of which reference isdirected to the accompanying drawings:

FIG. 1 is a plan view of the subject pump construction;

FIG. 2 is a side elevational view of the subject pump construction takenin the plane of line 22 of FIG. 1;

FIG. 3 is an end elevational view of the subject pump construction takenin the plane of line 33 of FIG. 1;

FIG. 4 is a vertical sectional view through the pump construction takenin the plane of line 4-4 of FIG. 2;

FIG. 5 is a vertical sectional view through the pump construction takenin the plane of line 5-5 of FIG. 2;

FIG. 6 is longitudinal vertical section through the pump constructiontaken in the plane of line 66 of FIG. 3;

FIG. 7 is a sectional view similar to FIG. 4 which illustrates internaldetails of a pump of modified construction.

Because of its novel internal construction to be described, the subjectpump is well suited for pumping all sorts of flowable products, such ascorrosive chemicals, fuels, oils and lubricants and other acid or alkaliproduts. Furthermore, due to the nature of the pumping elementsemployed, the products to be handled may vary from those of a very thickand viscous nature to those of a very fluid nature. In addition productswhich have discrete particles or lumps of solids included therein alsoare pumpable with this structure.

The subject pump is capable of either constant or variable productdisplacement and is operable at varying preselected speeds, dependingupon the capabilities of the Ice power source employed therewith.Likewise, the size of the pump may be varied to meet requirements. Thesubject pump, if the same is preadjusted as will be described, also mayact as a cut-off valve in which product displacement or flow ismaintained at zero. In addition, the direction of product flow throughthe pump may be readily and easily reversed as desired.

Summarizing the construction of the pump before describing the same indetail, the same embodies a pump housing in which is provided agenerally annular product flow or displacement passage. A product inletport communicates with the displacement passage at a first predeterminedlocation and a product outlet port communicates therewith at a secondpredetermined location. Positioned in the displacement passage formovement therein during pump operation are one or more deformable andresilient pumping elements which define and provide pockets or chambersin which product is to be carried through the pump. The pumping elementsare arranged to move in sequence past the inlet and outlet ports toeffect drawing of product into the passage and subsequently to effectdischarge of the same through the outlet port. To minimize element Wearand frictional drag during pump operation, the respective pumpingelements are independently rollable about their axes in the passage.

Various means may be employed for effecting movement of the pumpingelements in the displacement passage but it should be noted at theoutset that gears and other conventional and expensive mechanisms arenot employed with the subject construction. As a result, manufaoturingcosts are minimized due principally to the minimum machining operationsrequired.

The walls of the annular passage are defined by the spaced peripheralsurfaces of two members which are arranged one within the other. Therelationship of the walls to each other may be selectively varied inline with the volume of product displacement desired. Means foradjusting and varying the relationship between the passage walls areprovided in the subject pump construction. In this connection, thepassage walls desirably are generally of circular cylindricalconfiguration. When the respective walls are concentrically arranged,product displacement will be maintained at a predetermined minimum orzero. However, if the passage walls are eccentrically arranged productdisplacement may be effected through the pump in a predetermineddirection determined by the eccentric relationship of the walls.

Referring to FIGS 1 through 3, the subject pump comprises a compact forkshaped casing 1 which has extending axially thereof an integral pair ofspaced diametrically opposed arms 2 and 3. A hollow boss 4 projects fromthe casing in the direction opposite from the spaced arms for thepurpose to be described.

A cylindrical pump housing 6 is positioned between the arms of thecasing and is mounted for selective adjustable movement therebetween.Means are provided in conjunction with the arms of the casing which areengageable with the outer surface of the housing to effect suchadjustment. In the embodiment illustrated such means comprises a pair ofthumb screws 7 and 8 which have extensions 9 and 11 threadably receivedthrough threaded bores provided in arms 2 and 3 of the casing. Suchextensions terminate in heads 12 and 13 which engage the housing atdiametrically opposite locations and cooperate in maintaining thehousing immovable in a preselected location.

It is preferred that the housing is movable relative to the casing in agenerally straight path, which desirably is defined by a line extendingbetween the casing arms. For this purpose a housing guide bar 16 isremovably engaged by means of screws 17 with the respective ends of thespaced arms 2 and 3 of the pump casing to maintain the housing in suchpath during movement thereof.

Referring now to FIGS. 4 and 6 which illustrate a preferred embodimentof the invention, it will be noted that housing 6 is provided with aninner periphery 20 generally in the form of a right circular cylinder.It is this inner peripheral surface of the housing which defines theouter wall of a product displacement passage 21 through which productbeing pumped is flowable.

The end of housing 6 which is spaced from casing 1 is closed off by agenerally circular plate 22 which is held in place against the end ofthe casing by an annular cap 23. Desirably, a leak preventing rubber orlike material O-ring 24 is positioned in an annular recess defined bythe housing end, the cap 23 and the circular closure plate 22 held inplace thereby. As shown in FIG. 6, cap 23 is provided with internalannular shoulders 25 adapted to receive the housing end, the closureplate and the sealing ring as described.

Cap 23 is slidably receivable over the end of the housing and isretained in position thereon by the guide bar 16 mentioned previously.To gain access to the interior of the housing, it is merely necessary toremove guide bar 16 by disengaging screws 17 from the pump casing armsand to slide the plate 22 and cap 23 therefrom. In this connection, whenguide bar 16 is removed, the entire housing may be separated from thepump casing so that pump maintenance and pumping element replacement,when necessary, is facilitated.

As seen in FIGS. 1 and 3, the rim of cap 23 is provided with guide barreceiving slot structure defined by a pair of diametrically arrangedslots 26 and 27 in which guide bar 16 is slidably located. When thumbscrews 7 and 8 are backed off from engagement with the housing, thehousing may be moved in the straight line direction defined by theparallel side surfaces of the guide bar 16 for a purpose to bedescribed.

Product leakage at the end' of the housing adjacent casing 1 isprecluded by means of a preformed rubber or like sealing gasket 31 whichis interposed between a preformed metal bearing plate 32 and a generallyannular bearing surface 33 of the casing. Desirably a small pin 34 orlike fastening means (FIG. is secured to casing surface 33 and extendsthrough sealing gasket 31 and bearing plate 32 and precludes movementthereof relative to each other.

Still referring to FIG. 6, boss 4 of the casing is provided with athrough bore 36 in which are spacedly located a pair of oilless bearings37 and 38 respectively. A shaft 39 rotatably extends through thebearings. Such shaft is provided with a planar surface 41 intended to beoperatively engaged with a power source, such as an electric motor, foreffecting pump operation.

To insure the product being pumped will not leak from casing 1 throughbore 36, a coil spring 42 is positioned around shaft 39 between thebearings. The spring is compressed so that the same urges in oppositedirection a pair of metal washers 43 and 44. A pair of annular sealingrings 46 and 47 of rubber or like material surround shaft 39 and areinterposed between washers 43 and 44 respectively and a second pair ofannular Washers 48 and 4-9, which in turn are engaged with ends ofbearings 37 and 38. These latter washers are annularly beveled so thatthe action of spring 42 tends to force the sealing rings 46 and 47radially to wedge the same against the shaft 39 and bore 36 to precludeproduct leakage.

Positioned internally of housing 6 and spaced from the inner periphery2'9 thereof is a member 51 which cooperates with the housing in definingthe product displacement passage 21 mentioned previously. Such member51, as seen .in FIG. 4, has a generally right circular cylindrical outerperiphery 52 which defines the inner wall of the product displacementpassage.

In the pump embodiment illustrated in FIGS. 4 and 6, cylindrical member51 is directly secured to the inner end 4 of rotatable shaft 39 so as tobe directly rotatable thereby. That is, member 51 serves as a rotormember which rotates relative to the pump housing.

At this stage, it should be understood that housing 6 may be moved alongthe direction defined by guide bar 16 as described previously betweenpositions of concentric relationship and eccentric relationship relativeto rotor member 51. Such movement will result in a predetermined portionof the housing inner periphery 20 at one side of the pump being broughtinto proximity to a predetermined portion of the periphery ofcylindrical rotor member 51 while the diametrically opposite portions ofthe rotor and housing peripheries are moved away from each other. Due tothis construction, member 51 and housing inner periphery 20 may beselectively concentrically arranged or selectively eccentricallyarranged in one of two directions relative to the reference location inwhich the surfaces are concentric.

As a result, the walls of annular passage 21 may be selectivelyconcentrically or eccentrically arranged. When such walls are eccentricrelative to each other they diverge for a predetermined peripheralextent of the passage and converge for the remaining extent of thepassage. Because the surfaces which define the passage walls desirablyare circular cylindrical in configuration, when the rotor member iseccentrically arranged relative to the housing inner periphery thepassage walls diverge for approximately and converge for the remaining180, as best seen in FIG. 4.

Referring again to FIG. 6 it will be noted that casing 1 is providedwith a pair of generally diametrically opposite product ports 56 and 57through which product may be introduced into and carried away from thepump. Desirably ports 56 and 57 are internally threaded to securely andthreadably receive ends of product conduits (not shown).

Generally circular port extensions 58 and 59 are provided in the casingwhich extend generally at right angles to ports 56 and 57 respectivelytowards housing 6. As best shown in FIG. 5, bearing plate 32 is providedwith a pair of opposite generally arcuate apertures 61 and 62. A pair ofsimilar but slightly larger apertures 63 and 64 are provided in sealinggasket 31. Product ports 56 and 57 communicate directly with the annularpassage 21 provided in pump housing 6 through these aligned apertures.

Referring now to FIGS. 4 and 6, means are provided in annular passage 21for effecting movement of product between port 56, which is the intakeport of the embodiment as illustrated, and port 57, which is the outletport of the embodiment as illustrated. Such means comprises at least oneand desirably a plurality of pumping elements 65 each of which isdeformable and resilient so as to be capable of readily, rapidly andrepeatedly changing shape as the same move between the alternatelydiverging and converging passage walls during pump operation.

Each pumping element 65 desirably is of hollow tubular construction sothat each element is provided with an internal product carrying pocket66 for the reception and carrying of the product being pumped. Whilevarious materials may be employed for the deformable pumping elements,such as natural or synthetic rubber or various commercial plasticproducts, a material found well suited for this purpose is marketedunder the trade name Tygon and is manufactured by US. Stoneware Co. ofAkron, Ohio. This material is a synthetic vinyl plastic which iscommercially available in tubular form of various lengths and diameters.Tygon is well suited because of its strength, elasticity andflexibility, as well as its toughness and resistance to variouscorrosive media. As plastic materials such as Tygon are available inmany different formulations, the exact formulation chosen will bedetermined by the nature of the product being metered by the pump.

While the tubular pumping elements 65 prior to insertion in thedisplacement passage 21 of the pump are of generally cricular crosssection, the configuration of the elements is somewhat flattened intogenerally elliptical shape when the elements are inserted into the pumpand are frictionally engaged between the inner and outer walls of thedisplacement passage. As seen in FIG. 6, the elements desirably are of alength substantially equal to the axial length of passage 21. Uponrotation of rotor member 51 in the direction of the arrow of FIG. 4, thepumping elements will be moved in a circular path about the rotor memberin the same general direction as the rotor moves. However, at the sametime the pumping elements move about the axis of rotor member 51, theyare rolled about their own axes by the rotor in the direction of therespective arrows shown thereon.

This arrangement is generally analagous to a well known epicyclic geartrain arrangement with rotor member 51 acting as the rotating sun gear,the casing 6 acting as the stationary ring gear, and the respectivepumping elements acting as planetary gears interposed therebetween.Because of the relationship of this construction to a gear train asmentioned, a definite speed ratio reduction of 2:1 is obtained betweenrotation of shaft 39 and the pumping elements rollably moved thereby.This factor is important in that it permits power source and prime movereconomy.

FIG. 4 further shows that the respective pumping elements are maintainedspaced from and independent of each other during operation of the pump.This condition produces additional product carrying pockets 67 betweenadjacent pumping elements. With this construction, the product iscarried internally of the hollow elements and also between adjacentelements.

Means desirably is provided for maintaining the desired spacing betweenadjacent elements. In the embodiment of FIGS. 4 and 6, such spacingmeans comprises a series of freely rotatably cylindrical rods 68interposed between adjacent pumping elements. Such rods may be of metal,such as steel, a suitable wear resistant plastic, or other non-metallicmaterial, such as wood. These rods rotate generally about their own axesin the direction of the arrows shown thereon while at the same time theyare moving about the housing axis during pump operations.

It should be understood that as the respective pumping elements rollpast inlet port extension 58 upon rotation of rotor 51 that a change inpressure results due to such movement which produces a suction or vacuumat that location which results in product being drawn into and aroundthe respective pumping elements. Such product thus drawn in is carriedby and between the pumping elements through the passage to the generallydiametrically opposite position at which it is discharged through outletport 57.

That is, when the pump housing 6 is laterally shifted in a predetermineddirection as illustrated in FIG. 4 so that the rotor member 51 and pumpcasing inner periphery 20 are eccentrically arranged, the shape of therespective elements will be continuously modified as the same movethrough the alternate converging and diverging extents of thedisplacement passage. As a pumping element is moved through passage 21,the cross-sectional configuration thereof will vary between thegenerally elliptical configuration shown to the right of FIG. 4 and theflattened elliptical configuration shown to the left of FIG. 4. That is,the respective elements are periodically changed in shape so as to bedistended in the circumferential direction and contracted in the radialdirection as the same move into and through the converging extent of thepassage and vice versa as the same move into and through the divergingextent of the passage. As a result, product drawn into or between theelements will be forced therefrom as the elements pass through theconverging extent of the displacement passage.

As further shown in FIG. 4, the generally arcuate apertures 61 and 62through bearing plate 32 of the pump are positioned so that the samerespectively commence and stop adjacent the two locations at which thepassage walls are most closely related to each other and least closelyrelated to each other when the walls are 'eccentrically arranged. As aresult, product will be drawn into and between the respective pumpingelements at the same begin to contract in the circumferential directionand distend in the radial direction. In similar fashion, product will bedischarged by the elements as the same distend in the circumferentialdirection and contract in the radial direction. This results inautomatic intake of product into the passage and discharge of productfrom the passage as the pumping elements alternately expand and flattenradially during pump opera-.

tion.

It should be understood that this pump construction also is capable ofoperating as its own valve. That is, when rotor member 51 and innerperiphery 20 of the housing 6 are concentrically arranged, substantiallyno product displacement therethrough will be effected by the pumpingelements. Any slight product displacement due to the effects ofcentrifugal force which may result can be overcome by shifting housing 6slightly beyond the concentric position to balance the centrifugal forceeffect and also to balance movement of residual product carried withinthe hollow pumping elements.

While in the embodiment shown in the drawings the pumping elements areof hollow tubular configuration, the same could be of solid deformableconstruction also. When of solid construction the pumping elements wouldhave no internal product carrying pockets but the spacing therebetweenwould still be adapted to receive the product therein so that theprimary function of the pump basically would remain unchanged.Irrespective of whether hollow or solid elements are employed, the sameare to be deformable and resilient. As a result, products havingdiscrete lumps or particles therein can be handled in that the pumpingelements can deform to accommodate the same between the elements and thepassage walls.

As seen in FIG. 4, pump housing 6 has been shifted to the right of theconcentric position relative to the rotor member 51 so that port 56 willserve as the product inlet port when the rotor member is rotated in theclockwise direction. It should be understood, however, that if thehousing were shifted to the left of the concentric position relative tothe rotor member that the same clockwise rotation of such member wouldthen result in reverse product flow so that the inlet port would then beport 57 and the outlet port would then be port 56. This factor isimportant in that the direction of product displacement may be readilyand rapidly modified as desired merely by adjusting the thumb screws 7and 8 to effect shifting of housing 6 to the right or left to give theproduct flow direction desired.

As an example of an important use of this aspect of the development,reference is directed to the schematic flow arrangement shown inconjunction with FIG. 4. Because the direction of flow of productthrough the pump is reversible the same is highly effective for mixingtwo or more products. For example, if a mixing tank is connected byconduits to port 57 and a predetermined quantity of a first product ispositioned in such tank in any desirable manner, and if thereafter thepump housing is shifted to the right as seen in FIG. 4 to draw apredetermined quantity of a second product from a supply tank into port'56 and through the pump and discharge the same through port 57 into themixing tank, mixing of two products therein may be readily efiected.Thereafter, the same pump may be employed to withdraw the thoroughlymixed products from the mixing tank merely by shifting the housing toeccentrically offset the same in the opposite direction so thatdeformation of the respective pumping elements relative to ports 56 and57 will be reversed and the mixed products will be drawn from the mixingtank and transported back to the supply tank or to some other location.

In this connection, while thumb screw means have been illustrated forcontrolling the shiftable adjustment of the housing and rotor member 51relative to each other, it should be understood that other mechanismsmay be employed for effecting such shifting. If desired, pneumatic orhydraulic systems, servo motors or solenoids could be employed to effectrapid and automatic shifting of the housing from one position toanother.

It should also be understood that the amount of eccentricity between thewalls of the displacement passage will determine the rate of productdisplacement therethrough with maximum eccentricity producing thelargest flow volume.

As noted previously, the pumping elements are frictionally positionedbetween the rotor member 51 and the housing periphery so as to bedrivably engaged therewith. If desired, the periphery of the rotormember and also the periphery of the housing may be roughened, knurledor otherwise modified to increase the frictional driving contacttherebetween so that rolling of the elements will be insured. It wouldalso be possible to provide the exterior of the rotor member 51 withteeth and to extrude the tubular pumping elements with cooperableexternal teeth for eifecting a positive driving contact therebetween.However, because this latter alternative would increase the overall costof the pump, it is not generally preferred. In this connection, the costof the subject pump is maintained at a minimum because little machiningis required on the elements thereof to ready the same for use.

While one embodiment of the means for driving the pumping elementsthrough the displacement passage has been shown in FIGS. 4 and 6,various other modified means also may be employed. In this connection,reference is directed to FIG. 7 which shows a modified drivingarrangement.

In this modified embodiment, the cylindrical member 71 which defines theinner wall of the displacement passage 21 is not rotatably driven but ismerely mounted as an idler roller on an end of a shaft 72 which is to beoperatively connected with the power source as described previously.However, connected to such shaft 72 for rotation therewith adjacent thepump casing 1 is a generally circular plate 73 which has projectinglongitudinally of the pump housing a plurality of spaced pins 74 each ofwhich is located internally of a pumping element 76 of the hollowtubular type described previously. With this construction it should beunderstood that upon rotation of shaft 72 and plate 73 therewith, pins74 will effect rotation of the pumping elements about and through theannular product displacement passage for effecting product flow in themanner described previously.

If desired, longitudinally extending spacing elements 77 may be fixedlymounted on plate 73 to rotate therewith in the displacement passage toinsure proper spacing and freedom from contact between adjacent pumpingelements during pump operation. in this connection while FIG. 7illustrates simultaneous use of both driving pins 74 and spacingelements 77 in the modified pump, it should be understood that the pinsand spacers can be used independently of each other to effect movementof the pumping elements. If the spacers are employed without the pins,the spacer elements will be effective to engage from the rear and rollthe pumping elements through the displacement passage. In otherrespects, the construction shown in FIG. 7 is generally the same as thatdescribed previously with pump housing 6 being laterally and adjustablyshiftable relative to the cylindrical idler member 71 in the same mannerpreviously described.

Fnom the foregoing, it should be noted that this invention involves anadjustable flow pump construction which embodies a displacement passagefor fluid products which has alternately converging and divergingextents. In such passage, at least one and preferably a plurality ofseparate freely rollable deformable pumping elements are located.Because such elements are free of direct physical connection with thepump driving means and are free to rotate about their own axes as theymove through the displacement passage, frictional drag between theelements and the passage walls as well as undue wear of the elements isgreatly decreased.

While several embodiments of the subject invention have been describedherein, it should be understood that modifications thereof which maybecome obvious to a person of ordinary skill in the art also arecontemplated as falling within the purview of this invention and thesame should be interpreted in light of the appended claims.

I claim:

1. A pump comprising a housing which has a product displacement passagetherein the walls of which diverge relative to each other through apredetermined extent of said passage and converge relative to each otherthrough another predetermined extent of said passage, a product inletport communicating with said passage at one location and a productoutlet port communicating with said passage at another location, adeformable and resilient pumping element movably positioned in saidpassage between the walls thereof, said element being fi'ictionallyengaged with said walls and rollable about its axis during movementthrough said passage, said element being adapted periodically to distendin one direction and contract in another direction and vice versa as theelement moves between the converging and diverging walls of saidpassage, and means mounting one of said passage walls for movementrelative to the other passage wall whereby upon movement of such onewall said element is rollably movable through said passage to cause suchdistention and contraction thereof.

2. A pump comprising a housing which has an annular product displacementpassage therein the walls of which diverge relative to each otherthrough a predetermined extent of said passage and converge relative toeach other through the remainder of said passage, a product inlet portcommunicating with said passage at one predetermined location and aproduct outlet port communicating with said passage at anotherpredetermined location, a plurality of separate deformable and resilientpumping elements movably positioned in said passage between the wallsthereof, said elements being frictionally engaged with said walls androllable about their respective axes therebetween, said elements beingadapted periodically to distend in one direction and contract in anotherdirection and vice versa as the same'move through said passage betwensaid converging and diverging walls, and means mounting one of saidpassage walls for move ment relative to .the other passage wall wherebyupon movement 'of such one wall said elements are rollably movablethrough said passage to cause such distention and contraction thereof.

3. A pump comprising a housing which has an annular product displacementpassage therein the walls of which diverge relative to each otherthrough a circumferential extent of about and converge relative to eachother through the remainder of said passage, a product inlet portcommunicating with said passage at one predetermined location and aproduct outlet port communicating with said passage at anotherpredetermined location, a plurality of separate deformable and resilientpumping elements movably positioned in said passage between the wallsthereof, said elements being frictionally. engaged with said walls androllable about their respective axes therebetween, said elements beingadapted periodically to distend in one direction and contract in anotherdirection and vice versa as the same move through said passage betweensaid converging and diverging walls, said elements being spaced fromeach other in said passage whereby product carrying pockets are providedtherebetween, means for maintaining said elements spaced during movementthereof through said passage, and means mounting one of said passagewalls for movement relative to the other passage wall whereby uponmovement of such one wall said elements are rollably movable positivelythrough said passage to cause such distention and contraction thereof.

4. The pump of claim 3 in which said elements are of hollow tubularconfiguration whereby additional product carrying pockets are providedinternally of said elements.

5. A pump in which the product flow may be adjusted and varied withinpredetermined limits comprising a housing which has an annular productdisplacement passage therein, said passage being defined by a generallycircular cylindrical outer wall and a generally circular cylindricalinner wall, said passage walls being eccentrically arranged so that saidwalls diverge relative to each other through a predetermined extent ofsaid passage and converge relative to each other through the remainderof said passage, a product inlet port communieating with said passagecommencing at a predetermined location adjacent the location at whichsaid eccentrically arranged walls are most closely related, and aproduct outlet port communicating with said passage commencing at apredetermined location adjacent the location at which said walls areleast closely related, a plurality of deformable and resilient pumpingelements movably positioned in said passage for rolling movement betweensaid passage walls, said elements having product carrying pocketstherebetween, means mounting one of said passage walls for movementrelative to the other passage wall whereby upon movement of such oneWall said elements are rollably movable through said passage and pastsaid ports, said elements periodically distendin-g in one direction andcontracting in another direction as the same are moved through saidpassage and vice versa to successively draw product into said housingand subsequently discharge the same therefrom, and means for selectivelymodifying the eccentric relationship betwen said passage walls wherebythe product displacement therethrough may be selectively varied.

6. A pump in which the product flow may be adjusted and varied withinpredetermined limits comprising a housing which has an annular productdisplacement passage therein, said housing having a generally circularcylindrical inner periphery which defines the outer wall of saidpassage, a generally circular cylindrical member positioned internallyof said housing and spaced from the inner periphery thereof, the outerperiphery of said member defining the inner wall of said passage, meansfor laterally moving said housing and member relative to each otherwhereby said member and said housing may be selectively eccentrically orconcentrically arranged relative to each other, a product inlet portcommunicating with said passage at a predetermined location and aproduct outlet port communicating with said passage at anotherpredetermined location, a plurality of deformable and resilient pumpingelements movably positioned in said passage each of which is distendablein one direction and contractable in another direction and vice versa asthe same move through said passage, means movable in said passage formaintaining said elements spaced during such distention and contractionthereof, and means mounting said cylindrical member for rotary movementrelative to said housing periphery whereby upon rotation of such membersaid elements are rollably movable in unison through said passage pastsaid ports whereby product flow through said housing may be selectivelyeffected in relationship to the eccentric arrangement of said passagewalls.

7. The pump of claim 6 in which said elements are frictionally engagedbetween said member and said housing inner periphery, and in which saidpump includes mechanism for rotating said member within said housing 10whereby sad elements roll within said passage upon rotation of saidmember.

8. A variable discharge pump through which a flowable product may bemoved selectively in quantities variable from zero to a predeterminedmaximum, comprising a pump casing, a housing operatively engaged withsaid casing and slidably adjustable relative thereto, said housinghaving a generally circular cylindrical inner periphery, a rotor memberwhich has a generally circular cylindrical outer periphery positioned insaid housing and rotatably supported therein on a shaft which extendsthrough said casing into said housing, said inner periphery of saidhousing and said outer periphery of said rotor member defining outer andinner walls respectively of an annular product displacement passageprovided therebetween, a product inlet port extending through saidcasing into said housing into communication with said passage at a firstpredetermined location, and a product outlet port communicating withsaid passage at another predetermined location and extending therefrominto and through said casing, a plurality of hollow generally tubulardeformable and resilient pumping elements rollably positioned in saidpassage for movement therein past said inlet and outlet ports, saidhollow elements providing product carrying pockets therein, spacer meansmounted for movement in said passage for maintaining said elementsseparated whereby additional product carrying pockets are providedbetween adjacent elements, said elements being frictionally positionedbetween and engaged with the walls of said passage and being rollabletherebetween, and means mounting said housing for sliding adjustmentrelative to said rotor member whereby said housing and rotor member maybe concentrically arranged or selectively eccentrically arranged in oneof two directions relative to each other, said pump when said housingand rotor member are eccentrically arranged in one direction beingcapable of efiecting product displacement through said passage from saidinlet port to said outlet port, said pump when said housing and rotormember are eccentrically arranged in the other direction being capableof reversing the direction of such product displacement, suchdisplacement being generally zero when said housing and rotor member areconcentrically arranged.

9. The pump of claim 8 in which said housing is provided with a guideslot at an end thereof, and a guide bar located in said slot, said barbeing secured to said caslilng and holding said housing adjustablyengaged therewit 10. A pump structure which includes an annular productpassage defined by two generally circular cylindrical peripheralsurfaces of two members which comprise said structure one of which isarranged within the other, prod uct inlet and outlet ports through saidstructure in communication with said passage, means for moving rotatablyone of said members and its peripheral surface relative to the other,deformable pumping elements positioned in said passage for movementtherein, said elements being frictionally engaged between said surfacesand rollable therebetween in response to rotation of said one surface,and means mounting said two members for adjustment relative to eachother, whereby said surfaces of said members may be selectivelyconcentrically or eccentrically arranged, said structure being capableof producing product displacement from zero to a predetermined maximumdepending upon the relationship of said surfaces to each other, saiddisplacement being zero during operation of said structure when saidsurfaces are substantially concentrically related.

11. A pump comprising a housing having a product displacement passagetherein the walls of which converge relative to each other for apredetermined extent of said passage and diverge relative to each otherfor the remainder of said passage, product inlet and outlet ports incommunication with said passage at predetermined locations, a pluralityof deformable pumping elements positioned in said passage for movementpast said ports, each of said elements having a hollow generallyelliptical, crosssectional configuration whereby product canryingpockets are provided internally of said elements, said elements beingspaced from each other whereby additional product carrying pockets areprovided between adjacent elements, and means mounting one of saidpassage walls for movement relative to the other passage wall wherebyupon movement of such one wall said elements are rollably mos/ablethrough said passage past said ports, the cross-sectional configurationof each element periodically 12 varying between said generallyelliptical configuration and a distended and flattened ellipticalconfiguration as such element moves between said converging anddiverging walls of said passage, whereby product is drawn into saidpockets at said inlet port and discharged therefrom through said outletport.

References Cited in the file of this patent UNITED STATES PATENTSMcDuffie Apr. 21, 1959

